The present invention relates to a disk player for reproducing an optical disk signal including CD, LD, DVD, etc. More particularly, the present invention relates to a disk clamping mechanism automatically compatible to both of a large diameter disk of 12 cm in diameter and a small diameter disk of 8 cm in diameter.
When one disk to be reproduced is manually inserted into an insert port, automatic operation is carried out from carrying the disk to a turntable to claming the disk. After the end of reproduction, in a disk player for ejecting the disk by automatic operation, a clamping mechanism must be positioned upwardly via a gap from a disk top face so as not to interfere with the disk face. In addition, the turntable must be positioned lower than the disk bottom face so that a central protrusion engaging with the disk does not inhibit invasion of the disk bottom face. Further, in order to interrupt external vibration, some gap must be ensured in the vertical direction of the disk face in consideration of the fact that an apparatus is placed in a floating state.
In addition, in order to make compatible with two types of disks of large and small diameters, it is necessary to provide a lock mechanism for identifying both of these disks from each other, and then, maintaining the environment set to be compatible with a respective one of the disks. This causes a mechanism to be more complicated and the number of parts to be increased because of the necessity of routine construction of an automated system using a plenty of peripheral instruments such as optical sensors, micro-switches, or solenoids. In addition, a housing space and cost thereof are increased.
In Japanese Patent No. 2955116, there is disclosed a disk loading device compatible with two types of disks having large and small diameters. In this disclosure, a rack gear 4 and a side face of a shift plate 11 are vertically arranged on the faces of a CD 12 and a CD 13, and thus, the dimensions in this direction cannot be reduced any more. Further, a mechanism including a stopper arm 8, a lock arm 9, and a stopper arm spring 8a inhibits the dimensions in the thickness direction vertical to the faces of the CD 12 and the CD 13 and reduction in the number of parts.
However, for a disk player which is used for a car or which is incorporated in a computer and is functioned, a market always requires light weight, compact design, higher reliability due to a simplified structure, and a low price.
Therefore, it is an object of the present invention to provide a mechanism which is compatible with two types of disks having large and small diameters, which reduces the number of parts with its simplified construction to minimize the dimensions in the thickness direction, and which is reliably actuated to be applied to a disk player with its low cost.
In order to achieve the above described object, a disk player according to the present invention comprises: a carriage mechanism for basically feeding a selected one of the small diameter and large diameter disks to a turntable; and a clamping mechanism for compressing the disk to the turntable.
The disk player according to the present invention comprises: a selection arm which abuts against the disk and which can be turned according to its disk diameter; a shift bar which abuts against the disk and which can be moved in a disk feeding direction; a startup arm which is engaged with the shift bar and which turns the shift bar to be interlocked so as to be movable in the disk feeding direction; inscribed cam means in which the startup arm is coupled with a clamp arm of the clamp mechanism via a cam, thereby restricting turning, the cam means being capable of engagingly locking the startup arm at a different position depending on the scale of the diameter of the disk to be fed; first biasing means for biasing the shift bar in a direction opposite to the disk feeding direction; and second biasing means for biasing the startup arm, thereby holding the arm at a different engagingly locked position of the inscribed cam.
In the disk player according to the present invention, with the above described construction, the disk moving the shift bar to be pushed against the biasing force of the first biasing means turns the selection arm and controls the startup arm. Then, the shift bar is restricted by the startup arm held at any of the engagingly locked position of the inscribed cam, whereby the centers of the disks having their different diameters are positioned at the same position.
Here, the first biasing means and the second biasing means are constructed to provide one tensile coil sprint in a tensile manner between the startup arm and the clamp arm. In addition, in the startup arm, a swivel shaft is slidably guided to the clamp arm by a straight groove provided at a right angle relevant to the advancement direction of the disk. In addition, a cam follower pin erected at a position spaced from the swivel shaft of the startup arm introduces swiveling of the startup arm while a slide contact is maintained with either of first and second cam portions provided at the inscribed cam corresponding to a respective one of the large and small diameters of the disk to be fed by the biasing force of the tensile coil spring. This cam follower pin is constrained to either of a first pocket and a second pocket provided at terminals of the first and the second cams, whereby movement of the startup bar is inhibited in cooperation with the swivel shaft restricted by the straight groove.
The present invention is characterized in that movement from the first cam portion of the cam follower pin to a second cam portion is carried out in planar movement following a path defined by longitudinal movement of the shift bar moving in a disk feeding direction and transverse movement of the startup arm together with swinging movement of the selection arm in a cooperative manner, and these movements are not carried out by a specified guide groove which is mechanically formed.